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We use the publicly available code CMBFAST as modified by L. Pogosian and T. Vachaspati to simulate the effects of wiggly cosmic strings on the Cosmic Microwave Background (CMB). Using the modified CMBFAST code which takes into account…

Astrophysics · Physics 2011-05-10 N. Simatos , L. Perivolaropoulos

We describe a class of observational strategies for probing the anisotropies in the cosmic microwave background (CMB) where the instrument scans on rings which can be combined into an n-torus, the {\em ring torus}. This class has the…

Astrophysics · Physics 2009-11-06 Benjamin D. Wandelt , Frode K. Hansen

The polarization of the Cosmic Microwave Background (CMB)is a powerful observational tool at hand for modern cosmology. It allows to break the degeneracy of fundamental cosmological parameters one cannot obtain using only anisotropy data…

Astrophysics · Physics 2007-05-23 M. V. Sazhin , G. Sironi , O. S. Khovanskaya

ABRIDGED: We introduce and analyze a method for testing statistical isotropy and Gaussianity and apply it to the WMAP CMB foreground reduced, temperature maps, and cross-channel difference maps. We divide the sky into regions of varying…

Astrophysics · Physics 2009-06-23 Bartosz Lew

The advent of high signal-to-noise cosmic microwave background (CMB) anisotropy experiments now allow detailed studies on the statistics related to temperature fluctuations. The existence of acoustic oscillations in the anisotropy power…

Astrophysics · Physics 2007-05-23 Asantha Cooray

The increasing precision of cosmological datasets is opening up new opportunities to test predictions from cosmic inflation. Here we study the impact of high precision constraints on the primordial power spectrum and show how a new…

Astrophysics · Physics 2010-04-08 Benjamin Gold , Andreas Albrecht

y-type spectral distortions of the cosmic microwave background allow us to detect clusters and groups of galaxies, filaments of hot gas and the non-uniformities in the warm hot intergalactic medium. Several CMB experiments (on small areas…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-13 Rashid A. Sunyaev , Rishi Khatri

We present two novel methods for the estimation of the angular power spectrum of cosmic microwave background (CMB) anisotropies. We assume an absolute CMB experiment with arbitrary asymmetric beams and arbitrary sky coverage. The methods…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-25 Elina Keihänen , Kimmo Kiiveri , Hannu Kurki-Suonio , Martin Reinecke

Results of a search for small-scale anisotropy in the cosmic microwave background (CMB) are presented. Observations were made at the South Pole using the Viper telescope, with a .26 degree (FWHM) beam and a passband centered at 40 GHz.…

We determine the full C_l spectra and correlation functions of the temperature and polarization anisotropies in the CMB, generated by a source modeled by the large N limit of spontaneously broken global O(N)-theories. We point out a problem…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Elisa Fenu , Daniel G. Figueroa , Ruth Durrer , Juan Garcia-Bellido , Martin Kunz

We present an efficient method to compute CMB anisotropies in non-flat universes. First we derive the Boltzmann equation for cosmic microwave background temperature and polarization fluctuations produced by scalar perturbations in a general…

Astrophysics · Physics 2009-06-16 Matias Zaldarriaga , Uros Seljak , Edmund Bertschinger

In our recent paper (Yadav et al. 2007) we described a fast cubic (bispectrum) estimator of the amplitude of primordial non-Gaussianity of local type, f_{NL}, from a combined analysis of the Cosmic Microwave Background (CMB) temperature and…

We briefly review certain aspects of cosmic microwave background anisotropies as generated in passive and active models of structure formation. We then focus on cosmic strings based models and discuss their status in the light of current…

Astrophysics · Physics 2009-11-07 Alejandro Gangui , Levon Pogosian , Serge Winitzki

Full-sky maps of the cosmic microwave background temperature reveal a 7% asymmetry of fluctuation power between two halves of the sky. A common phenomenological model for this asymmetry is an overall dipole modulation of statistically…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-07 Simone Aiola , Bingjie Wang , Arthur Kosowsky , Tina Kahniashvili , Hassan Firouzjahi

Probing correlations among short and long-wavelength cosmological fluctuations is known to be decisive for deepening the current understanding of inflation at the microphysical level. Spectral distortions of the CMB can be caused by…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Emanuela Dimastrogiovanni , Razieh Emami

The Cosmic Microwave Background Radiation (CMB) is an invaluable probe of the conditions of the early universe. Recent measurements of its spatial anisotropy have allowed accurate determinations of several fundamental cosmological…

Astrophysics · Physics 2009-09-29 Christopher O'Dell

A number of experiments for measuring anisotropies of the Cosmic Microwave Background use scanning strategies in which temperature fluctuations are measured along circular scans on the sky. It is possible, from a large number of such…

Astrophysics · Physics 2009-10-30 J. Delabrouille , K. M. Górski , E. Hivon

Bianchi VII_h models have been recently proposed to explain potential anomalies in the CMB anisotropy as observed by WMAP. We investigate the violation of statistical isotropy due to an embedded Bianchi VII_h templates in the CMB anisotropy…

Astrophysics · Physics 2008-11-26 Tuhin Ghosh , Amir Hajian , Tarun Souradeep

The standard cosmological model, which assumes statistical isotropy and parity invariance, predicts the absence of correlations between even-parity and odd-parity observables of the cosmic microwave background (CMB). Contrary to these…

Fluctuations in the intensity and polarization of the cosmic microwave background (CMB) and the large-scale distribution of matter in the universe each contain clues about the nature of the earliest moments of time. The next generation of…

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